Documentation

The streaming JSON reporter ingredient.

When activated via --streaming-json, replaces console output with newline-delimited JSON events streamed to stdout.

Ingredient that lists the test tree as JSON and exits without running tests.

Activated via --list-tests-json.

Default ingredients with streaming reporter added

Drop-in replacement for defaultMain that supports --streaming-json.

If you bypass this entry point and wire streamingIngredients manually, threat-model summaries will not appear in the JSON output unless you also call localOption (TMStoreOption (Just store)) . localOption (storeRecorder store) on your tree (with a freshly-allocated store from newTMStore).

Package root capture

The packageRoot field emitted on the SuiteStarted event is captured from the call site of defaultMainStreaming (typically the user's Main.hs) via HasCallStack. The mechanism is implemented in callerPackageRoot: read the top of callStack to obtain both the GHC package identifier of the calling module and the file path it was compiled from, then search the workspace (starting at the process working directory) for a directory containing both a matching <pkgname>.cabal file and the relative source file.

This is correct in the common case where the Main.hs entry point and the tests it assembles live in the same cabal package. It is not correct for cross-package test reuse — for example, if Main.hs in package A pulls in test trees defined in package B's library, those tests will be attributed to package A, not B. We explicitly accept this limitation; addressing it would require per-test source-location metadata (e.g. via Template Haskell or CPP at every test definition site), which is significantly more invasive.

If the resolution fails (e.g. the test is launched from a working directory that does not contain the package, or the package name cannot be extracted), packageRoot is omitted from the JSON output (consistent with the existing Maybe-as-absent-key convention).

Variant of defaultMainStreaming that allows callers to prepend additional ingredients (e.g. package-specific CLI option managers).

The same internal streaming wiring is always installed (threat-model summary store, trace recorder, shared output lock, and package root capture from call-site), then Tasty runs with:

extraIngredients <> streamingIngredients